Body Fat Calculator
US Navy method estimate using waist, neck, and (for women) hip measurements.
Free · No signup · Runs in your browser · Shareable link syncs inputs
Inputs
Updates live as you type — Calculate syncs a shareable URL.
Estimated body fat
16.5%
Fitness
Circumference method — measurement error is common. Category bands are rough adult male guidelines.
16.5
Fitness
EssentialAthleticFitnessAverageHigh
Balanced meals
30 min activity
Stay hydrated
7–8 hrs sleep
Screening only — not a medical diagnosis.
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How this calculator works
US Navy method estimate using waist, neck, and (for women) hip measurements.
How is it calculated?
US Navy circumference formulas using log10 of measurements in inches.
Example
Male 70″, neck 15.5″, waist 34″ → mid-teens to low-20s % depending on precision.
Frequently asked questions
Accurate?+
Rough estimate. DEXA/BodPod are more precise.